Ald. Joseph Moore, 49th, singled out the billionaire Koch brothers as the wrong type of owner for a Chicago newspaper. The Koch brothers, who are reported to be interested in buying some or all of Tribune Co.'s newspapers, support conservative political causes.

The liberal Moore, who sponsored the resolution, said the Tribune should go to a local investor who "gets the city, understands the city, and most importantly, ownership that does not carry a political agenda."

Tribune Co. emerged from bankruptcy under new ownership at the end of last year. In February, the Chicago-based media company hired investment bankers to manage inquiries for its eight daily newspapers, including the Tribune and Los Angeles Times.

Last month, Tribune Co. Chief Executive Peter Liguori sent an email to employees calling speculation about a transaction premature. About 40 parties have expressed interest in acquiring some or all of Tribune Co.'s newspapers, according to reports. .